Electrical system



Dec. 26, 1933. E, BQWLE'S 1,941,384

ELECTRICAL SYSTEM Filed Jan. 22, 1927 .Ec/warr/L. flowlea Patented Dec. 26 1933 n, w L nii .111 .i' m i:,--.-" rx'i.-: e r. are 7.1 I e present invention elates ele t i ts -t eetat nts ehe a sueplxiee the! cir uit; rn aneme hqds au more art eular mitqwsr th; d m. qmi iiffii weltilsee t uth dir ternsxand, d fi er n tea tfir latin et inql fi swe ls ass QQ QHP 'Eli QrD r nts to ram-t9 leave, nure iii q tt mteme ltem t new t??? P QEQ t e le m n its: From a more limited aspect,,theginver tign re ;ist

, lates to rectifying systems and Rectified a i uretta e-s at me l- C known, a su y. att n edt.wit r..'tesiclua r t eiyveaetst et r e e a e ewespnn te .i toe fllln ic k .fr p es tw u ir e fi dmc rre t itwt wi t s seli eai e e esit ieal exes. man ..-case t eseia es ha m u -trwh ek app ied. to o her, se .h were n beaa e 3 651w in ly.tr l some.smisp s i leits meme-the e: ppl s by. ,p esentand i-W l'1k Ql? ..;m hd$; 0f i .t -a 9w ar aluaa jde r lubuti uqhw uxsee zt pw e {t nt s iwit circuit 4:" Owing to the presence 'of the alter atm e rr et liat erera iewhets s Miter.- ence of alternating potentialbetween the vegxe twensiz bettearer eaes fiend? sm il.

The resulti sttha the wip keam manual ways. present n commercia m r-M i, el reaties tetw ea;

A object ,orthe resent n en on, he efpnem tma he lep i Cis t ia 9i til-ten t? '1 is to...imiqrqve up mpres ntr ax eleetrisats r maste mind e q eim itA- yflga i t e anee i t -.bed eiar t e ther 1 5 3 1 3 be d fi eme 2Q tems and methodswof theabpge describgdmhar ,of the vertexes l4 ,thealternatr 1, acter. to. .theend hatith i ;.e. l c ne ma .b u .p .1: 1-1 been 're ystlpnrg se ri gntthe a h nced and-.theirte onemmincreased; .a l ,am .11.. .1. th. the;a qver ndcqth s piec sti ev ewtas 1 newss ee srsil ravere are e ette willfl et ereinaftet ex ained,..a reams: their ze teetm eeeee- 4 9.1- btie si ht flit inventioar sid s-in the-meanin M an me- 1 2. i141 9 -ll i dni t exeleelaeert e so bridge...=. Th ;-.ll mb fid .al erna na and. d etr-w h t, ma e @Ilfiq A: 'B r "19 :9u J t u ents:- e t r the-br e byway-cf. tw epnom wiltrays 11F?! ..-.,1 9 d e= si vertexes, a the 0 l.s WQ-. DD9$it.-$ 1131; ri ls iiiqllitvrlh PilielQPiKllQn-W jr texes of the bridge are so chosen that a zero G k-Q WMWB bridge 9 P,.-,

direct current,--freed now "from the a trnatigg current,will travel to any desired load, after which itv will return, by the conductor 34, to the bridge vertex 16, and thence, by the arm 28 and the conductor 36 of the circuit 2, back to the generator 8. e i

It will be understood, of course, that the Wheatstone bridge must be so designed as to suppress the alternating voltage, but to permit free passage for the direct current. To this end, the arms of the bridge are supplied with imped .ances 38,. 40, 42 and 44. The condensers 18and may be regarded as part of the impedances and 44'; but as their purpose is merely to prevent passage of direct current along the arms 22 and 24, it is preferred to disregard them in the dis cussion and, therefore, to have their reactances quite small or negligible with respect to the impedances 40 and 44. Now, the impedances of the bridge may be balanced at one frequency and unbalanced at another, which' would mean that alternating currents of only a particular frequency or frequencies would be balanced out by this arrangement. If, however, the four reactbridge by way of these two other vertexes. In the specific embodiment of the invention that is hereinafter illustrated and described, the di- 'r'ect current is prevented from entering two opfposite arms of the bridge by the use of con-' densers. f

The invention will now be described in connection with the accompanying drawing, in which mg. l is a diagrammatic view illustrating the principle of the invention, and Figs. 2 and 3 are similarviews showing the invention applied to 1 radio-receiving systems.

The present invention is applicable wherever it is desired to separate out, or filter, alternating currents from a mixture of alternating and direct currents. Let it be-assumed, .in Fig. 1, that such a mixture ofcurrents is flowing in the circuit 2. Then, according to the present 501 invention, a second circuit 4 will be provided in which the direct currents only from the circuit 2 will be transmitted. This result will be attainedby the use of a Wheatstone-bridge ar-- rangement 6, as will presently be described. 1 To fix the ideas, a direct-current, commutator :d iensvare;not. .in;-.pxecti. emve .y we emiea m ae ele eliwia kni e w imeet fg he m .1

30 alternatingpotential shallsexist between them.

Direct current only, therefore, will leave the 32.9; thgg rguit q Eromthe conduc ,32,,the,.

vice 52, and from-the input circuit, intothe out-- put or load circuit 60. The output circuit must.

have a source of direct current. Batteries are customarily used for such purpose. do to have even comparatively slight alternatingcurrent ripples with this direct current, for the space-current device will amplify these ripples,

and thus produce an objectionable extraneous.

sound in the reproducer or lo'ud speaker.

Alternating-current sources of energy. are iusu-fally more convenient than batteries, and may readily-be used according to the present invention. Thealternating-current energy from any 5 source 62-may be transmitted through a trans-- former64 into a circuit-66-to whichthe-v'ertexes .10and-l2 of the Wheatstone bridge may be connected. A rectifier 68*may be used torectify this alternating current and the bridge will eliminate the residual ripples-.- The resulting direct cur-- rent may be supplied into the output circuit by connecting it with-the vertexes 14 and 16 of the bridge.

It is sometimes desirable to cause the Wheatstone bridge circuit to have no-efiect on the external plate circuit impedance ofthe tube 52.

This can be accomplished by the insertion of the by-pass condenser '76 which, has "an impedance negligible compared with the impedance as measured between the vertexes l4 and 16 of the bridge.- This condenser in no way affects the bpration of the Wheatstone bridge circuit.

The energy from the output circuit may, if desired, be transmitted to the input circuit "70 01'. a second'space-current device '72 that may be coupled to the space-current device 52, inductive- ..ly, for example, as by means of a-transformer.

'14. Intact, any desired number of-space-current devices may be so connected; The condenser '76 all the output circuits.

voltage for any number of space-current devices.

It Will not- Individual Wheatstone bridges may, however, be introduced in each plate circuit, as shown in Fig. 3. Any alternating signal voltage applied to the vertexes 14 and 16 of each balanced Wheatstone bridge will produce zero potential differences between the vertexes 10 and 12 of each bridge. The vertexes l0 and 12 may therefore all be connected in parallel to the same rectifying circuit 66without in anyway causing a coupling among the individual plate circuits. These individual Wheatstone bridges act simultaneously, however, as coupling impedances between the .output circuit of any particular tube and the inputcircuit of the succeeding tube. In this manher, the output circuits of the tubes are rendered mutually =exclusiveiand can not be coupled together due to any impedance in the power source or power-supply leads. An impedance 78 serves .to prevent blocking of the space-charge device 72 through the accumulation of a negative charge on-the grid 80.

Modifications will' occur topersons skilled in I plurality of space-current devices each having an inputcircuit -and-'an output circuit, the output ing connected with the other two opposite vertexes oia separate Wheatstone bridge, and-the Wheatcircuit of each ofthe-space-cur-rent devices be- I stone bridges serving'to couple the output circuit of one space-current device with theinput circuit of another space-current device.

2. An electric system having, in combination, a-plurality of space-current devices each having an input circuit and an output circuit and connected together in-cascade', with "a common power source for the output circuits, and Wheatstoneof onesp'ace-current device withthe input circuitof another space-current device to prevent space-current devices.

EDWARD L. BOWLES.

'bridge means for connectingthe output circuit coupling of the output circuits of the said two is connected so as to serve the same; function for A single Wheatstone bridge may thus be employed as a source of plate 

